Description of problem:
With the lastest xorg package, can count on a hard hang at some point.  I saw
this the first time when starting firefox after the package update.  The last 3
hangs occured when switching desktops.  Thought this was on this a single
machine, but get this on a similar machine at work. 

No indication in any log, sysrq is enabled but has no affect. :-/

Version-Release number of selected component (if applicable):
xorg-x11.i386 6.8.2-1.FC3.13

How reproducible:
The longest I have been up without hang is 3 days, shortest was 20 minutes.

Steps to Reproduce:
1. bring up gnome session.
2. start lots'o windows
3. switch between desktops
  
Actual results:
Complete hang, no network, serial.  Must BWS.

Expected results:
No hang.  

Additional info:
austin.i$ cat /proc/cpuinfo
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 15
model           : 2
model name      : Intel(R) Pentium(R) 4 CPU 2.80GHz
stepping        : 9
cpu MHz         : 2800.883
cache size      : 512 KB
physical id     : 0
siblings        : 2
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 2
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat
pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe cid xtpr
bogomips        : 5554.17

processor       : 1
vendor_id       : GenuineIntel
cpu family      : 15
model           : 2
model name      : Intel(R) Pentium(R) 4 CPU 2.80GHz
stepping        : 9
cpu MHz         : 2800.883
cache size      : 512 KB
physical id     : 0
siblings        : 2
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 2
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat
pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe cid xtpr
bogomips        : 5586.94

$ cat /proc/meminfo
MemTotal:      1035452 kB
MemFree:         18812 kB
Buffers:        176716 kB
Cached:         513996 kB
SwapCached:        236 kB
Active:         639560 kB
Inactive:       282612 kB
HighTotal:      131008 kB
HighFree:          140 kB
LowTotal:       904444 kB
LowFree:         18672 kB
SwapTotal:     7978060 kB
SwapFree:      7977820 kB
Dirty:            6328 kB
Writeback:           0 kB
Mapped:         269048 kB
Slab:            69796 kB
CommitLimit:   8495784 kB
Committed_AS:   632608 kB
PageTables:       3708 kB
VmallocTotal:   114680 kB
VmallocUsed:     10356 kB
VmallocChunk:   102900 kB
HugePages_Total:     0
HugePages_Free:      0
Hugepagesize:     4096 kB

$ lspci
00:00.0 Host bridge: Intel Corp. 82865G/PE/P DRAM Controller/Host-Hub Interface
(rev 02)
00:01.0 PCI bridge: Intel Corp. 82865G/PE/P PCI to AGP Controller (rev 02)
00:1d.0 USB Controller: Intel Corp. 82801EB/ER (ICH5/ICH5R) USB UHCI Controller
#1 (rev 02)
00:1d.1 USB Controller: Intel Corp. 82801EB/ER (ICH5/ICH5R) USB UHCI Controller
#2 (rev 02)
00:1d.2 USB Controller: Intel Corp. 82801EB/ER (ICH5/ICH5R) USB UHCI #3 (rev 02)
00:1d.3 USB Controller: Intel Corp. 82801EB/ER (ICH5/ICH5R) USB UHCI Controller
#4 (rev 02)
00:1d.7 USB Controller: Intel Corp. 82801EB/ER (ICH5/ICH5R) USB2 EHCI Controller
(rev 02)
00:1e.0 PCI bridge: Intel Corp. 82801 PCI Bridge (rev c2)
00:1f.0 ISA bridge: Intel Corp. 82801EB/ER (ICH5/ICH5R) LPC Interface Bridge
(rev 02)
00:1f.1 IDE interface: Intel Corp. 82801EB/ER (ICH5/ICH5R) IDE Controller (rev 02)
00:1f.3 SMBus: Intel Corp. 82801EB/ER (ICH5/ICH5R) SMBus Controller (rev 02)
00:1f.5 Multimedia audio controller: Intel Corp. 82801EB/ER (ICH5/ICH5R) AC'97
Audio Controller (rev 02)
01:00.0 VGA compatible controller: ATI Technologies Inc Radeon RV250 If [Radeon
9000] (rev 01)
02:02.0 Ethernet controller: Realtek Semiconductor Co., Ltd.
RTL-8139/8139C/8139C+ (rev 10)
02:04.0 Ethernet controller: Linksys NC100 Network Everywhere Fast Ethernet
10/100 (rev 11)
02:07.0 Unknown mass storage controller: Promise Technology, Inc. 20269 (rev 02)